We suggest that viroids are trapped into adaptive peaks as the result of adaptive constraints. The first one is imposed by the necessity to fold into packed structures to escape from RNA silencing. This creates antagonistic epistases, which make future adaptive trajectories contingent upon the first mutation and slow down the rate of adaptation. This second constraint can only be surpassed by i...

Viroids, small single-stranded circular RNAs (246-401 nucleotides), do not have mRNA capacity and must recruit host proteins to assist in the steps of their biological cycle. The nature of these cellular factors is poorly understood due to a lack of reliable experimental approaches. Here, to screen for host proteins interacting with viroid RNAs in vivo, we UV-irradiated avocado leaves infected ...

A novel virus-like sequence from grapevine was identified by Illumina sequencing. The complete genome is 7,551 nucleotides in length, with polyadenylation at the 3' end. Translation of the sequence revealed five open reading frames (ORFs). The genomic organization was most similar to those of vitiviruses. The polymerase (ORF1) and coat protein (ORF4) genes shared 31 to 49% nucleotide and 40 to ...

Apples are the third most produced fruit in world, behind bananas and oranges, terms of volume. Over past ten years, Serbia's apple production has nearly doubled. less subjected to viral viroid attacks than other species. Most viruses cause no visible symptoms on plant's organs, trees either seem be good condition or, case sensitive cultivars, their yield is reduced. Apple stem pitting virus (A...

MIKC(C)-type MADS box genes encode transcription factors that play crucial roles in plant growth and development. Analysis of the grapevine (Vitis vinifera) genome revealed up to 38 MIKC(C)-type genes. We report here a complete analysis of this gene family regarding their phylogenetic relationships with homologous genes identified in other sequenced dicot genomes, their genome location, and gen...

Plasmopara viticola, the causal agent of grapevine downy mildew, is one of the most devastating grape pathogen in Europe and North America. Although phytochemicals are used to control pathogen infections, the appearance of resistant strains and the concern for possible adverse effects on environment and human health are increasing the search for alternative strategies. In the present investigat...